IR spectrum of protonated ovalene (7-C_32_H_15_^+^)

DOI

The mid-infrared emission from galactic objects, including reflection nebulae, planetary nebulae, proto-planetary nebulae, molecular clouds, etc, as well as external galaxies, is dominated by the unidentified infrared (UIR) emission bands. Large protonated polycyclic aromatic hydrocarbons (H^+^PAHs) were proposed as possible carriers, but no spectrum of an H^+^PAH has been shown to exactly match the UIR bands. Here, we report the IR spectrum of protonated ovalene (7-C_32_H_15_^+^) measured in a para-hydrogen (p-H_2_) matrix at 3.2K, generated by bombarding a mixture of ovalene and p-H_2_ with electrons during matrix deposition. Spectral assignments were made based on the expected chemistry and on the spectra simulated with the wavenumbers and infrared intensities predicted with the B3PW91/6-311++G(2d,2p) method. The close resemblance of the observed spectral pattern to that of the UIR bands suggests that protonated ovalene may contribute to the UIR emission, particularly from objects that emit Class A spectra, such as the IRIS reflection nebula, NGC 7023.

Identifier
DOI http://doi.org/10.26093/cds/vizier.18250096
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/ApJ/825/96
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/825/96
Related Identifier https://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/825/96
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/ApJ/825/96
Provenance
Creator Tsuge M.; Bahou M.; Wu Y.-J.; Allamandola L.; Lee Y.-P.
Publisher CDS
Publication Year 2016
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Interdisciplinary Astronomy; Natural Sciences; Observational Astronomy; Physics